The present invention relates to a soft grip cap for a rotatable torque adjusting device of a rotary tool and to soft grip keyless chuck assemblies for use with the rotary tool.
In conventional hand-powered, electric-powered, and pneumatic-powered tool drivers, adjustable chucks are used for holding a tool such as a drill bit. A conventional chuck has a conical body threaded onto the drive shaft of the rotary tool. Three jaws spaced circumferentially 120° apart from each other are constrained in passageways defined by the chuck body. The spacing between the jaws is adjusted by rotating an adjustment ring, which encircles the chuck body. Such a chuck is keyless when the adjustment ring is rotated by hand. Keyless chucks typically have a front sleeve and a rear sleeve.
In addition, most tool drivers are provided with a torque adjusting device to allow the user to adjust the output torque provided by the rotation tool. The torque adjusting device is usually formed with a clutch cap or ring, which the user grasps to rotate and to adjust the torque. The torque adjusting device cooperates with the chuck such that when the torque adjusting device is adjusted the output provided to the chuck is likewise adjusted. Indications may be provided on the clutch cap to indict the torque set by the adjusting device.
It would be desirable to provide a quality gripping surface for each or both of the clutch cap and the chuck. Several attempts have been made to provide grip boots having high coefficients of friction for improving the user's grip on a chuck, especially a keyless chuck. For example, U.S. Pat. Nos. 5,452,906 and 5,476,273 each discuss the use of grip boots for improving the user's grip on a chuck.
One problem associated with these soft grip chucks is the fact that the soft grip material is not very durable. When using a drill having a soft grip chuck to drill in a small constrained location, incidental contact of the rotating chuck with another object, such as an obstructing portion of the workpiece, may damage the soft grip material. This excessive wearing and damaging of the soft grip is very undesirable. One approach to address that problem is shown in U.S. Pat. No. 5,882,016. There, ribs are provided on the sleeve such that they extend radially outward beyond the elastomeric material to protect the elastomeric material from wear.